Brown azo dyestuffs.



UNITED STATES PATENT OFFI 1;

KARL SCHIRMACHER AND HEINRICH ELVERT, or noons'r-oiv-Tnnain,,qnn NY,

ASSIGNORS To FARBWERKE VORM. MEISTER LUCIUS & BRtINmo, OF HooHs'r-oN- THE-MAIN, GER-MANY, a CORPORATION OF GERMANY.

BROWN AZO DYESTUIEFS.

No Drawing. Application filed January Ph. D.,'chemist, and HEINRICH ELVERT, Ph.

D., chemist, citizens of the Empire of Germany, residing at; Hochst-on the-Main,Ger-

many, have invented certain new and useful Improvements in New Brown Azo Dyestufi's, of which the following is a specifica-- tion.

We have found that valuable azo dyestufls are obtained by causing a diazo compound of an aromatic amino-sulfid to act upon naphthalene-2-arylamino- 8 oxy 6 sulfonic acid. The dyestuifs thus obtained are brown powders, more readily soluble in hot than in cold water to a brown solution, and dyein wool fast brown tints.

glhe constitutijfn of said responds to theifermula:

new dyestufl's corwherein aryl aryl and aryl mean aromatic residues. In these dyestuffs the hydrogen atom of the sulfo group may, of course, be replaced by a metal. On reducing the dyestuffs withtin and hydrochloric acid,

' ing an aromatic sulfinic acid-with an aromatic base .(see Berliner Bem'chte vol. 36 I page 107 and following), are diazotized with 60 parts of hydrochloric acid of 20 B.

Specification of Iiettei's Patent.

Patented Oct. 21, 1913.

21913. SerialNo.739,881 I specific gravity and 7 part's'of sodium nitrite, a-nd the diazo solution, after it has been filtered, is introduced, while stirring, into a solution of 35 parts of naphthalene-2- phe'nylamino-8-oxy-6sulfonic acid and 70 parts of calcined sodium-carbonate. After the mixture has been stirred for several hours, it is. heated to 60-70 C., whereupon a small quantity of common salt is added and the sodium salt of the dyestufi" is isolated by filtration. The dyestuif thus obtained forms, when dry, a brownish-black powder, dissolving in water to a reddishbrown solution and dyeing wool fast brown tints. 'It' has the constitution:

and yields, on being split up with tin and hydrochloric acid, p-aminophenyl p tolylsulfid and naphthalene-Q-phenylamino-T-amino--8-oxy-6-sulfonic acid;

Having now described our invention what We claim is:

-1.' As new products, the azo dyestuffs the constitution of which corresponds to the general formula:

wherein aryl, aryl and aryl mean aromatic residues and X means a sulfo group, said dyestuffs being dark-brown powders, readily soluble in water to a brown solution, dyeing wool fast brown tints, and splitting up, when treated with tin and hydrochloric acid, into p-arylamino-arylsulfid and naphthalene 2 arylamino 7 amino-8-oxy -6-sulfonic acid.

the constitutioni being a; brown fiowder, i'a dil ysol uble in hat 10 water, dyeingjwool fast brown tints, and

splitting up, when t-reatd with tin and hydrb chloric acid, into ip ara-a min ophen ylpal a-tolylsulfid and 'naphthalenefl-phepyl In testlmony whreof, weafiix our signa- 15 tures inpresence of two witnesses.

KARL SCI-IIRM ACHER. .HEI'NRICH ELVERT.

Withessesi I JEAN GRUND,

CARL GRUND. 

